title: Mutation of Pseudomonas aeruginosa specifying reduced affinity for penicillin G.
abstract: A mutant of Pseudomonas aeruginosa strain PAO503 was isolated after ethane-methane-sulfonate mutagenesis and selection of ticarcillin. The mutant, PCC17, displayed reduced affinity for [14C] penicillin G at all of its penicillin-binding proteins as well as a general increase in resistance to all the beta-lactam antibiotics tested. The mutation designated pbpA has been mapped by FP-2-mediated conjugation and was located distal to the proA locus and 33% linked to it. The two loci were not cotransducible with phage F116L. PCC17 and exconjugants produced from it had similar phenotypes, displayed the reduced affinity for [14C] penicillin G, had similar resistance profiles, and had an increased amount of protein corresponding to penicillin-binding protein 6. On back mutation the pbpA locus reverted to the PAO503 phenotype.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002352:Carrier Proteins / Q000378:metabolism; D002463:Cell Membrane Permeability; D007769:Lactams / Q000494:pharmacology; D009152:Mutagenicity Tests; D009154:Mutation; D010400:Penicillin G / Q000378:metabolism*; D010403:Penicillin Resistance; D010641:Phenotype; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D002352:Carrier Proteins; D007769:Lactams; D010400:Penicillin G